Protective helmets comprising adjustability features are well known. In this regard, it is known to provide an adjustable helmet having two shell portions that are held together by screws. The loosening and tightening of the screws allow for adjustment of the helmet. In use, the two shell portions are fixedly held together, thus are adapted to move relative to one another when the screws are loosened. When the desired size is obtained, the screws are tightened and the two shell portions are locked in place. The two shell portions usually have overlapping surfaces to enable the shell portions to be moved relative to one another while not leaving any gap between the two shell portions. Shock-absorbing foam padding is positioned inside the helmet shells to cushion the wearer's head. For practical reasons, there are usually two sections of padding: One section of padding being attached to each shell portion of the protective helmet. This arrangement simplifies the assembly of padding and shell portions and also facilitates assembly of the components.
An important drawback of this known configuration is that the overlapping surfaces of the two shell portions create a step or ridge on the inner surface of the shell assembly directly above the head of the player. More particularly, in the area of the separation of the two shell portions, the interior curvature of the helmet shell is broken by the feature of adjustability of the helmet. This seems to create an area of concentration of forces. When an impact occurs, the step or ridge has a tendency to dig into the foam padding and apply a localized force to the head of the wearer, which is highly undesirable in a protective helmet. A protective helmet's main task is to spread the force of impact to as wide a surface as possible without bottoming out, in order to absorb impact and prevent injuries to the cranium.
A second drawback of this known configuration of an adjustable helmet is the reduced amount of foam padding at the junction of two padding sections. For practical reasons, the foam padding sections separation coincides with the shell portions separation. This arrangement entails that when the shell portions are spaced apart, a gap is formed between the padding sections in the area where the two shell portions overlap each other. As a result, certain circumstances may leave an area of the cranium with insufficient shock-absorbing foam padding and therefore more limited protection. Some helmets have been designed with no padding separation. The necessary gap for adjusting the shell portions is located at the back of the head which may leave the back portion of the cranium with insufficient shock-absorbing foam padding.